flame, repeat-
able fuel ignition, low maintenance (no moving parts), and low cooling-/combustion-air
requirements.
The SureFire gas igniters are NFPA-rated as a Class 1, 2, or 3 igniter, depending on the applica-
tion: Class 1 igniters are used for burner light-up and support under any conditions; Class 2 igniters
are used for light-up and support under prescribed light-off conditions; and Class 3 igniters are used
for light-up only and are not intended for warm-up or support.
These igniters are provided with a durable High Energy Igniter (HEI) for repeatable light-off. Refer
to the HEI bulletin for detailed HEI information.
In most applications, the self-contained SureFire gas igniters are mounted in a burner through a
mounting tube. The major components of the SureFire gas igniters are the guide tube assembly,
and the HEI. Figure 1 shows the SureFire igniter assembly.
FIGURE 1.
SureFire Model 20 Gas Igniter Assembly
REF
153.9 (6.06)
REF
1.69
REF
L REF
(1.88)
O.D. REF
(2.94)
74.7
QUICK-
RELEASE
FLANGE
CLAMP
TO HEI
CONNECTING
CABLE
HEI SPARK
ROD
ASSEMBLY
GAS PILOT
ORIFICE
GUIDE
TUBE
47.8
SIGHT
PORT
COMBUSTION
COOLING
AIR HOSE
CONNECTION
HEI SPARK ROD TIP
MUST BE FLUSH WITH
FURNACE SIDE OF
BAFFLE PLATE
BAFFLE
1/2" NPT
GAS HOSE
CONNECTION
DIMENSIONS IN MM (INCHES)
PLATE
GAS
TUBE
DIMENSIONS mm (in)
3/4" NPT
SF-100
OCTOBER 24, 2007 2
®
TABLE OF CONTENTS
DESCRIPTION ...............................................................................................
1
TABLE OF CONTENTS ................................................................................
2
DESCRIPTION (continued)............................................................................
3
SPECIFICATIONS..........................................................................................
3
SUREFIRE IGNITER SPECIFICATION PROCEDURE ..............................
4
SUREFIRE MODEL 20 GAS IGNITER........................................................
4
SUREFIRE 20 ORDERING INFORMATION...............................................
7
SAFETY..........................................................................................................
9
INSTALLATION.............................................................................................
9
COMMISSIONING ......................................................................................
11
OPERATION.................................................................................................
12
TROUBLESHOOTING ................................................................................
13
MAINTENANCE..........................................................................................
13
STORAGE.....................................................................................................
14
SUREFIRE MODEL 20 OUTPUT CURVE.................................................
14 3
®
DESCRIPTION (continued)
Guide Tube Assembly
The guide tube assembly contains the working parts of the igniter and houses the gas transport tube,
baffle, and HEI spark rod.
Gas is transported down the guide tube through the gas transport tube and is distributed to the pri-
mary combustion zone. A small orifice upstream of the baffle releases a small amount of gas to mix
with the cooling/combustion air.
Cooling/combustion air is transported down the guide tube and mixes with the gas at the baffle plate
to form a combustible mixture.
Ignition first occurs at the spark tip and then spreads to the gas transport tube opening at the tip end
of the igniter. Combustion is completed 2 to 3 feet into the furnace.
Mounting Tube (optional)
The mounting tube (Figure 4) is welded to the burner front plate in most cases, and supports the
igniter assembly. The igniter guide tube slides into the mounting tube and is secured in place by a
split clamping ring (squeeze collar), which is bolted to the mounting tube. The squeeze collar also
acts as a packing gland follower.
High Energy Igniter (HEI)
The HEI spark rod provides a 12-joule spark, which ignites the gas/air mixture. The HEI consists of
a fouling-resistant surface gap spark tip connected to a positioning rod, power unit, and cable. (See
HEI bulletin for details.)
View Port
An integral view port is provided on the head of the SureFire igniter.
SPECIFICATIONS
SUREFIRE 20
Fuel
Natural gas/propane
Guide Tube OD
1.88
Mounting Tube OD
2.13
Capacity Rating (MBTU/hr.)
1.0
Fuel Supply Requirements (psig)
10 psig
Cooling/Combustion Air Supply
12 SCFM@3> windbox
Cooling/Combustion Air Pressure
(inches w.c. measured at the sight port)
0.5
Cooling/Combustion Air Connection
3/4 NPT, female
Cooling/Combustion Air Pressure
Measurement Port
1/8 NPT, female
Material of Construction
304 Stainless Steel (except for gas transport tube and HEI Rod).
Ignition Method
High Energy Igniter (HEI), 12 joule
NFPA Class
1, 2, or 3
Recommended Gas Hose Size
3/4
Gas Hose Connection
1/2 NPT, female
Gas Line Strainer (FNPT)
0.33 4
®
SUREFIRE IGNITER SPECIFICATION PROCEDURE
A complete Fireye gas igniter assembly will consist of at least three part numbers, each ordered sep-
arately. These include the SureFire 20 Gas Igniter, the High Energy Igniter (HEI) power pack, and
the HEI interconnecting cable.
Optional accessories, ordered separately, include the Mount Tube, Air Hose, and Gas Hose.
SUREFIRE MODEL 20 GAS IGNITER
The SureFire gas Igniter is sized to fire natural gas with an output of 1.0MBTU/hr at a pressure of 10
psig (690 millibars).
Each igniter comes with a 1.88" (48 mm) OD guide tube assembly, HEI spark rod, 1/2" NPT gas
inlet connection, 3/4" NPT cooling/combustion air inlet connection. Air flow of 12 SCFM @ 3"
W.C. above Windbox pressure is required through the guide tube at all times
The HEI cable and HEI power pack must be selected from the HEI component list to provide a com-
plete working assembly.
Mounting the igniter to the burner front plate can be done several different ways;
1.
The guide tube can be welded to the burner front plate.
2.
A mount plate fabricated on site, can be welded to the guide tube and that assembly can be
welded or bolted to the burner front plate.
3.
A mount tube with packing gland can be welded to the burner front plate. Then the igniter is
inserted into the mount tube and allowing the packing gland to be tightened around the guide
tube.
FIGURE 2.
SureFire Model 20 Gas Igniter
Length L is the distance from the firing tip of the igniter back to the break point of the rear flange.
In selecting the length of the SureFire Gas Igniter, there are two dimensions that make up the total
length of the igniter. One is the distance from the firing tip back to the burner frontplate, and the sec-
ond is the distance from the burner front plate back to the rear flange. The total of these two dis-
tances will equal dimension L of the igniter. The first dimension is dependent on the burner size
and must be measured or taken from a burner dimensional drawing. As a general rule the firing tip of
a gas igniter can be located 6" (153mm) behind the oil gun. If a bluff body diffuser is used to stabi-
lize the flame, the igniter must be mounted flush with the diffuser/stabilizer. Refer to the chart below
for the igniter set back dimensions. This igniter can be used in a Class 1, 2 or 3 in either a continuous
or intermittent application.
14 (350)
Min
DIMENSIONS in (mm)
L
FRONT PLATE 5
®
Table 1:
GAS IGNITER SET BACK DIMENSIONS IN INCHES (Distance from Oil Gun Tip)
Select a length L that will allow a minimum of 6" (153 mm) from the burner front plate back to the
rear flange.
MOUNT TUBE (Optional)
Mount tube, 2.13" (54 mm) OD, carbon steel, with packing gland and locking collar, suitable for
welding to the burner front plate. The mount tube is optional equipment and is not required unless
the owner intends to periodically remove the complete igniter from the burner front.
GAS HOSE (Optional)
Fireye can provide a flexible stainless steel hose, 0.5" (13 mm) ID, with single braid stainless steel
jacket, a 0.5" (13 mm) NPT nipple connection to igniter and a 0.75" (19 mm) NPT nipple connection
to the gas supply.
AIR HOSE (Optional)
Fireye can also provide a reinforced 1" ID rubber air hose with a 1" NPT nipple connection to air
supply at one end, and hose clamps at both ends. The air hose is required to supply cooling/combus-
tion air to the igniter.
IGNITER
CLASS
NO OIL GUN STABLIZER - IN (MM)
SWIRLER TYPE STABLIZER - IN (MM)
BLUFF BODY DIFFUSER- IN (MM)
1
6 (153)
0
0
2
6 (153)
0
0
3
6 (153)
6 (153)
0 6
®
FIGURE 3.
SureFire 20 GAS IGNITER
14 (350mm)
Min
CLAMP P/N 13-382
2.13 (55mm)Dia
SUREFIRE 20
P/N SF20-XXX
AIR HOSE
10 (3.0m) P/N 59-495
BURNER FRONT PLATE
MOUNT TUBE
P/N MT20 -XX
CLOSE
NIPPLE
P/N 35-309
QUICK DISCONNECT PLUG
P/N 10- 211
PRESSURE TESTER
QUICK DISCONNECT SOCKET
GAS HOSE
CABLE
15 (4.5m) P/N SF1-CA1-15*
P/N 9-438
P/N 148- 21
4 (1.2m) P/N GH20-04
6 (1.8m) P/N GH20-06
8 (2.4m) P/N GH20-08
SPARK TIP
Short 8 P/N
*Long 27 P/N 145-19
8 (203mm) or
27 (685mm)
8(203mm)
10
(250mm)
POWER PACK
P/N SF1-1 (110 VAC NEMA 4)
P/N SF1-2 (220 VAC NEMA 4)
P/N SF1-3 (110 VAC NEMA 4X)
P/N SF1-4 (220 VAC NEMA 4X)
GASKET P/N 29-403
145-18
*(used with gas igniters 38 and longer)
*Refer to ORDERING INFORMATION,
page 7, for list of available lengths
(OPTIONAL) 7
®
SUREFIRE 20 ORDERING INFORMATION
Referring to Figures 2 and 3 and Part Number listings:
1.
Select the appropriate igniter length.
2.
Select optional SureFire gas igniter accessories.
3.
Select the appropriate HEI Power Pack (See page 8).
4.
Select